*-----------*
|1.4|...|...|
|..8|...|.2.|
|.9.|.87|4..|
|---+---+---|
|.43|..5|...|
|...|341|...|
|...|9..|64.|
|---+---+---|
|..2|67.|.3.|
|.3.|...|9..|
|...|...|8.6|
*-----------*